Energy Units Energy Units More Introduction Many sorts of units are used in energy discussions. They fall into two broad categories: (a) those whose definition is not related to a particular fuel, which we here term "basic" units; and (b) those whose definition is related to idealized properties of a specific fuel, which we here term "source-based" units. These units, along with special topics related to electricity, are discussed in succeeding sections. Table 1 gives conversion factors between units, as well as the energy content of specific fuels. Basic Units Joule (J). This is the basic energy unit of the metric system, or in a later more comprehensive formulation, the International System of Units (SI). It is ultimately defined in terms of the meter, kilogram, and second. Calorie (cal). Historically the calorie was defined in terms of the heating of water. Thus, in a traditional definition, one calorie is the amount of heat required to raise the temperature of 1 gram of water by 1°C, from 14.5 °C to 15.5 °C.

(This is sometimes referred to as the 15 °C calorie, and differs slightly from the "calorie" measured for other temperature intervals.) More recently the calorie has been defined in terms of the joule; the equivalence between the calorie and joule is historically known as the mechanical equivalent of heat. Several definitions of the calorie are now in common use, including (2): thermochemical calorie 1 cal = 4.1900 J The International Table (IT) calorie has been adopted in the publications of the Energy Information Administration of the U.S. Department of Energy (DOE/EIA) (3) and of the International Energy Agency of the Organization for Economic Co-operation and Development (OECD/IEA) (4). In view of the importance of these publications, it is reasonable to view the IT calorie as being the preferred unit for discussions of energy production and use, but there is no universally adopted practice (see also the discussion of Btu, below). Sometimes a capitalized version, Calorie, is used to denoted the kilocalorie (kcal). In discussing food, the "calorie," capitalized or not, is always the kilocalorie. British thermal unit (Btu).

This is the English system analog of the calorie. For specific heat capacities to be the same, whether expressed in Btu/lb-°F or in cal/gm-°C: 1 Btu = 251.9958 cal. As for the calorie, there is a family of "Btu's" in relatively common use, including: thermochemical Btu 59 °F (15 °C) Btu 1 Btu = 1054.80 Again, the IT unit is the one used in DOE/EIA publications. Kilowatt-hour (kWh). The kilowatt-hour is a standard unit of electricity production and consumption. By definition, noting that 1 kilowatt = 1000 watts: 1 kWh = 3.6 x 10 6 J (exact). The relationship between the kWh and the Btu depends upon which "Btu" is used. It is common, although not universal, to use the equivalence: 1 kWh = 3412 Btu. This corresponds to the International Table Btu.

[More precisely, 1 kWh = 3412.14 Btu (IT).] Large-scale units. In describing national or global energy budgets, it is common practice to use large-scale units based upon the joule, Btu, and kWh: Exajoule (EJ): 1 quad = 1015 Btu = 1.055 EJ Terawatt-year (TWyr): 1 TWyr = 8.76 x 1012 kWh = 31.54 EJ = 29.89 quad Source based conversion factors and units Actual energy content and nominal equivalents. In discussing the production and use of energy it is often convenient to speak in terms of the bulk amount of fuel, e.g. a barrel of oil or a ton of coal. These terms are sometimes used not only to denote a volume or mass, but also to represent an amount of energy. While useful in putting a primary focus on the fuel of interest, there is an intrinsic imprecision in such an approach because "oil" and "coal" embrace a variety of products, with different energy contents per unit mass. The differences can be large.

The heat content for several common fuels, as well as the weighted averages for petroleum, coal and natural gas consumed in the U.S. in 1995, are listed in Table 1, using data from Ref. (3). Given the wide variations in the actual heat content of fuels, especially oil and coal, it is common to introduce a nominal energy equivalent that reflects a typical energy content of the given fuel, but is decoupled from the variations that occur in actual fuels . The energy equivalent can be considered to be an alternate energy unit, precisely related to units such as the joule, calorie, or Btu. Energy equivalents for oil and coal are discussed in succeeding paragraphs, below, and are listed in Table 1. Conversion factors for oil. The heat content of crude oil from different countries varies from about 5.6 million Btu (MBtu) per barrel to about 6.3 MBtu (5). The heat content of typical petroleum products varies even more (see Table 1). A nominal conversion factor is sometimes used for a barrel of crude oil, which is close to its actual average energy content: 1 barrel of oil equivalent = 5.80 MBtu.

With this definition, a correspondence can be established between millions of barrels of oil per day (Mbd) and quads per year: 1 Mbd = 0.0058 x 365 = 2.12 quad/yr. which is sometimes rounded off to: 1 Mbd = 2 quad/yr. An energy equivalence for oil can also be specified in terms of energy per metric ton (tonne). [For oil, unlike coal, mass is commonly specified in tonnes even in U.S. literature (5).] The number of barrels of crude oil per tonne varies widely, depending upon the source. For 1993, the EIA has reported values varying from well under 7 barrels/tonne for some countries of origin to over 8 barrels/tonne for others (5). For the United States, the average was 7.33 barrels/tonne. This average, together with the nominal equivalence of 5.8 MBtu/bbl, corresponds to a heat content for crude oil of 42.5 MBtu/tonne. There are differing definitions in the literature of a tonne of oil equivalent (toe).

In OECD/IEA publications it is set equal to 10.0 kcal (IT) (4), while in other publications it is set equal to 10.7 x 106 kcal (thermochemical) [e.g., Ref. 6] . These choices correspond, respectively, to: 1 toe = 1.00 x 1010 cal (IT) = 41.868 GJ = 39.68 MBtu (IT) and 1 toe = 1.07 x 1010 cal (thermochemical) = 44.769 GJ = 42.46 MBtu (thermochemical). In OECD/IEA tabulations, the megatonne of oil equivalent (Mtoe), equal to 4.1868 x 1016 J, is used as the general unit to describe the energy content of all fuels.

A corresponding larger unit, the gigatonne of oil equivalent (Gtoe) can be related to the exajoule and quad: 1 Gtoe = 41.868 EJ = 39.68 quad. Conversion factors for coal. Amounts of coal are described both in short tons and metric tons. Heat contents vary widely among countries, averaging less than 10 MBtu/ton for some regions and up to about 30 MBtu/ton for others, where low heat content corresponds to a large lignite fraction (5). For the United States in 1995, the average was 20.9 MBtu/ton (3). In a fairly widely used specification of a nominal value, the energy content of 1 tonne of coal equivalent is set equal to 7 x 109 calories [e.g., Ref. 6].

Then, at a level of precision that makes the particular choice of "calorie" irrelevant: 1 tonne of coal (equiv) = 29.3 GJ = 27.8 MBtu 1 ton of coal (equiv) = 26.6 GJ = 25.2 MBtu. As seen in Table 1, this nominal heat content is considerably higher than the average heat content of coal as presently consumed in the United States; it is, however, fairly close to the average heat content of coal used in the early 1950s (3). Conversion factors for natural gas. Natural gas is made up largely, but not entirely, of methane (CH4) and its energy content is more uniform than that of coal. For the large majority of sources the gross heat content of dry natural gas lies between 900 Btu/ft3 and 1100 Btu/ft3 (5). For the U.S. in 1995, it averaged 1028 Btu/ft3 (3).

There is no widely used equivalent unit of energy specifically based on natural gas, although the heat content of natural gas is often approximated by the rounded value of 1000 Btu/ft3. In discussions of natural gas production and consumption it is also common to use the unit therm, where 1 therm = 100,000 Btu. Special topics relating to electricity Gross and net electricity production. The gross electricity generation (for example, in kWh) is the amount of energy measured at the terminals of the generating unit. The net generation is measured at the output transformer of the power plant. They differ by the amount of electricity consumed within the plant itself, roughly 4%. Electricity sales. Electricity sales differ from net generation due to transmission losses. In standard tabulations, such as those of the DOE/EIA, there may be further differences due to imports, exports, time lags between generation and billing, and the inclusion in utility sales of amounts of electricity purchased by utilities from non-utility producers for resale. In 1993, for example, the ratio of U.S. utility sales to net utility generation was 0.99.

Transmission and distribution losses amounted to about 8%, but this was largely balanced by purchases from non-utility electricity producers and, secondarily, imports (3). Efficiency for fossil fuel and nuclear sources. At 100% efficiency, the conversion from heat to electricity is at a rate of 3412 Btu per kWh. Actual generation efficiencies, limited by the Second Law of Thermodynamics and design practicalities, fall short of this. More specifically, for U.S. power plants during recent years the average heat input per kWh of net generation was in the neighborhood of 10,300 Btu/kWh for fossil-fuel steam plants and of 10,700 Btu/kWh for nuclear plants, corresponding to thermal conversion efficiencies of 33% and 32%, respectively (3). [It is expected that future plants, especially those based on gas turbine systems, often will have higher efficiencies, in some cases exceeding 50%.] Primary energy and end-use energy.

In considering energy consumption for electricity generation, a separation is sometimes made between the electrical energy consumed at the point of use (converted from electricity sales at the rate of 3412 Btu/kWh) and the energy lost to heat in electricity generation and transmission. The end-use energy and the energy losses are then individually tabulated, with the losses roughly twice as great as the end-use energy. However, this separation creates a possibly misleading asymmetry in comparisons among modes of energy use, because end-use losses are neglected for fossil fuels used directly and these losses sometimes are substantial. From the standpoint of energy resources, the interesting number is the primary energy---the total energy consumed at the generating plant, whether used efficiently or wasted. Thus, it is usually desirable to consider energy budgets in terms of the energy content of the resource originally consumed, i.e., the primary energy and not the end-use energy. When this is done, the energy corresponding to 1 kWh of electricity depends upon the conversion efficiency, and is typically above 10,000 Btu. Energy equivalent for non-fossil fuel sources. To facilitate comparisons between different energy sources, a conversion factor is assigned to non-fossil fuel sources which relates electricity generated to a nominal primary energy.

For nuclear energy, this is done on the basis of the heat content of the steam produced (3). A similar approach can be used for geothermal plants. For the various renewable energy sources, the primary energy cannot be readily established and often is irrelevant. Instead, a "primary energy" is assigned by adopting a standard conversion factor---equivalent to adopting a nominal efficiency, where 100% efficiency corresponds to 3412 Btu per kWh. In DOE/EIA publications, the nominal efficiency for renewable energy sources (hydroelectric, biomass, wind, photovoltaic, and solar thermal) is taken to be the same as the efficiency of fossil-fuel steam electric plants, namely 33.2% (3). [More precisely, the conversion factor is set at 10,272 Btu/kWh.] In OECD/IEA publications, on the other hand, the efficiency is taken to be 100% for hydroelectric, wind, and direct solar sources; for geothermal sources it is taken to be 10% (4).

Thus, compared to DOE/EIA publications, the OECD/IEA publications underestimate the primary energy consumed for hydroelectric power and overestimate the primary energy consumed for geothermal power. [The DOE/EIA and OECD/IEA assumptions are summarized in Table 1.] Gigawatt-year (GWyr). Large individual plants have capacities in the neighborhood of 1 GW of electrical output (GWe). This makes the gigawatt-year (GWyr) a natural unit to use in discussions of total electricity production. By definition: 1 GWyr = 8.76 x 109 kWh. It is to be noted that a 1 GWe plant does not normally generate 1 GWyr of electricity per year. The ratio of the actual electricity generated to the amount which would be generated were the plant to operate at full capacity for one year is the capacity factor. Typical coal and nuclear plants operate at capacity factors between about 60% and 80%.

For a plant with a conversion efficiency of 33%, an electrical output of 1 GWyr (3.15 x 1016 J) corresponds to a thermal output of 9.5 x 1016 J, or 0.090 quad. Thus, typically, the relation between primary energy used and electricity produced is approximately: 1 quad ---> 11 GWyr. a. 1 MBtu = 106 Btu (IT); 1 GJ = 109 J b. 1 cord of dry wood = 1.25 ton c. Ignoring n-capture in 235U and 238U. References * This chapter is based, to a large extent, on Reference 1. David Bodansky, "Appendix: Energy Units," in The Energy Source Book, Ruth Howes and Anthony Fainberg, editors (New York: American Institute of Physics, 1991). Handbook of Chemistry and Physics, 77th Edition, 1996-1997, David R. Lide, editor-in-chief (Boca Raton: CRC Press, 1996). U.S.

Department of Energy, Annual Energy Review 1995, Energy Information Administration Report DOE/EIA-0384(95) (Washington, D.C.: U.S. DOE, 1996). Organization for Economic Co-operation and Development, International Energy Agency, Energy Balances of OECD Countries 1992-1993 (Paris: OECD, 1995). U.S. Department of Energy, International Energy Annual 1993, Energy Information Administration Report DOE/EIA-0219(93) (Washington, D.C.: U.S. DOE, 1995). Energy In a Finite World, A Global Systems Analysis, W. Häfele, Program Leader, Report by the Energy Systems Program Group of the International Institute for Applied Systems Analysis (IIASA) (Cambridge, MA: Ballinger, 1981). Why is energy not an SI base unit? - Physics Stack Exchange Why is energy not an SI base unit? According to a textbook I have begun to read, there are seven base SI units: Length Electric current Luminous intensity What I do not understand is, why have these been chosen as the fundamental units?

It seems to me that mass, amount, current and luminous intensity could all be expressed with energy. Instead energy is for some reason a derived unit. Why is this? 1 I'm not sure how you could express amount (particle number) and current (charge flow) in terms of energy? – jabirali Feb 23 '15 at 4:29 I was thinking at a particle level, since matter is made of energy, multiple particles together as an amount would still have an associated energy, and charge flow could be measured as how much work the moving charges could do. – Segmented Feb 23 '15 at 4:40 @Segmented: not really, since two different circuits can be doing different amounts of work with the exact same current (because the resistance is different). You can certainly measure how much work the moving charges do, but current is the rate of movement of charge, not the work it does. So you'd still need another fundamental unit in addition to energy, to use to derive a unit for current (resistance or potential difference).

– Steve Jessop Feb 23 '15 at 15:53 1 Oh, unless you mean that one amp could be defined as $5.6 \times 10^{-12}$ kg of electrons per second, or something. Converting with $e = mc^2$ I think that's 511kW. I fear this would be confusing, considering that the mass of the electrons isn't what we're interested in ;-) – Steve Jessop Feb 23 '15 at 16:01 1 @SteveJessop While not what I said that is indeed along the lines I was thinking =) – Segmented Feb 23 '15 at 16:57 Amount of a substance Luminous intensity are pretty much bogus fundamental units. The unit temperature is just an expression of the Boltzmann constant (or you could say the converse, that the Boltzmann constant is not fundamental as it is merely an expression of the anthropocentric and arbitrary unit temperature). The unit energy will be whatever is the unit of force times the unit of length. A Joule is the same as a Newton - Meter , which are already defined in the SI system.

You should read the NIST page on units to get the low-down on it. In my opinion, electric charge is a more fundamental physical quantity than electric current , but NIST (or more accurately, BIPM ) defined the unit current first and then, using the unit current and unit time , they defined the unit charge . I would have sorta defined charge first and then current. Just like the unit charge (or current) is just another way to express the vacuum permittivity or, alternatively the Coulomb constant and the unit temperature is just another way to express the Boltzmann constant, the unit time, unit length, and unit mass, all three taken together could be just another way to express the speed of light , the Planck constant , and the gravitational constant .

But because $G$ is not easy to measure (given independent units of measure) and can never be measured as accurately as we can measure the frequency of "radiation corresponding to the transition between the two hyperfine levels of the ground state of the caesium 133 atom", we will never have $G$ as a defined constant as we do for $c$ and as we will soon for $\hbar$ and perhaps for $\epsilon_0$ and $k_\text{B}$. But once we define length, time, and mass independently, we cannot define energy independently. The Joule is a "derived unit". EDIT: so i will try to explain why the candela is bogus. (i had already for the mol .) so there is a sorta arbitrary specification of frequency, then what is the difference between 1 Candela and $\frac{4 \pi}{683} \approx$ 0.0184 watts? bogus base unit. up vote 12 down vote why have these been chosen as the fundamental units? Courtesy of the National Institute of Standards and Technology (NIST), we have some historical context .

It basically boils down to wanting to have absolute measurements with respect to units of mass, length, and time. These few were originally chosen because these form a set of mutually independent dimensions. That is to say, it is from these three that many common (at the time, though still often today) terms could be derived (velocity, acceleration, momentum, energy, etc)--though a few other units require other fundamental units (e.g., temperature). Instead energy is for some reason a derived unit. Why is this? Because energy is derived from other more primitive variables. From Wikipedia's article on Fundamental units Many of these quantities are related to each other by various physical laws, and as a result the units of some of the quantities can be expressed as products (or ratios) of powers of other units (for example, momentum is mass multiplied velocity while velocity is measured in distance divided by time). These relationships are discussed in dimensional analysis. Those that cannot be so expressed can be regarded as "fundamental" in this sense) So, since energy is the product of a few variables (e.g., $E=\frac12mv^2$ or $E=mg\Delta h$ or what have you), it cannot be a fundamental unit.

up vote 4 down vote One Joule (the unit of energy) equals one $ \ $ kg m$^2$/s$^2$. So, you see, a unit of energy can be expressed in terms of units of mass, distance, and time. The people who chose the SI units could have made, for example, the Joule an SI basic-unit and could have defined the unit of mass in terms of distance, time, and energy (kg = Js$^2$/m$^2$). But then we would still have the same number of fundamental units. So the choice of which SI units to define as basic units is somewhat arbitrary. Though, I think that energy was not chosen as an SI basic-unit because it just doesn't seem as fundamental as time, mass, or distance. up vote 3 down vote Purely historical and convenience reasons, people standardized measures that were more obvious from real life (remember, quantum mechanics and relativity didn't exist when SI was drafted). It's actually arbitrary how many quantities you define as fundamental (and associate them with base units), and it doesn't matter which ones are they. In quantum mechanics energy is actually used as a base quantity (measured in $eV$).

They say you effectively set $c=\hbar=1$ and then mass, energy, momentum, frequency and temperature are all measured in eV. Time and distance are also sometimes measured in $eV^{-1}$ instead of seconds & meters if that's more convenient. Velocities are nondimensional (fractions of the speed of light). Each unit you define as a base unit comes with an associated "natural constant" that wouldn't be needed, if you unified two units of measurement. If you measure temperature in units of energy, the need for Boltzmann constant (the conversion factor) disappears. Similarly, space and time can be measured in the same units if you standardize the conversion velocity (usually the speed of light) to be equal to $1$. Then, you have $\hbar$ that converts between units of frequency and energy (and other related pairs). The unit electric charge connects amperes with the mechanical units.

In the purest form, there would be only one physical unit, and the only natural constants would be the dimensionless strengths of the elementary forces, and relative rest masses of elementary particles - these are the only things that must be given, not derived (so far - hopefully we'll get to the grand unification theory someday). up vote -1 down vote The whole notion of "fundamental units" is bogus, physics can be formulated in a purely dimensionless way. Given any set of equations, you are free to define new variables by e.g. introducing arbitrary scaling constants. This then allows you to study certain scaling limits of the theory. E.g. starting from special relativity (formulated in natural units), you can introduce a dimensionless parameter c to zoom in into the low velocity limit of the theory (you scale all the velocities but such that in terms of the new variables the values the velocities take remain constant as you scale the real velocities down to zero). Exactly at the scaling limit, certain equations relating physical variables will become singular. Unable to relate these quantities to each other, stupid physicists living at approximately that scaling limit may think that they are fundamentally incompatible and need to be measured in units with incompatible dimensions.

Dimensional analysis as taught in most textbooks is wrong in the sense of "not even wrong". While formally correct, the argument made is not correct, because in natural units you can always relate any physical quantity to another. So, why are the results then still correct? The way the period of a pendulum depends on its length L and the local gravitational acceleration can only be found if you assume that hbar, G and c will not appear in the equations in SI units. But, from what I pointed out above, this must follow from an appropriate scaling argument. So, it's that scaling argument that is the only physically correct argument, not the given "dimensional calculus" argument. Units of Measurement - Energy-101.org Units of Measurement Units of Measurement THIS IS THE FIRST LAW OF THERMODYNAMICS. Energy can neither be created nor destroyed, it can only be converted from one form to another. KINETIC ENERGY is motion energy.

POTENTIAL ENERGY is energy stored in matter ENERGY IS MEASURED IN JOULES(J) 1 BTU= 1,055 Joules POWER IS MEASURED IN WATTS (W) 1 Watt= 1 Joule/second JOHN STIVERS – WORK ENERGY POWER – This video breaks down WORK, ENERGY and POWER into an easily understood explanation. Well let’s start with work. Physicists define work as a force applied over a distance. If you take an object, say a toolbox and apply a force, 22 pounds of force and you move it two feet, you’ve done 44 foot pounds of work. In metric those units convert to 100 newtons of force, and let’s say we moved it 0.60 of a meter. So we’ve done 60 newton-meters of work. In the metric system that’s referred to as a joule, 1 newton-meter is 1 joule. Continue reading the transcript.

energy-101.org (video and transcript link) energy-101.org by Dennis Silverman ~silverma 1 Joule (J) is the MKS unit of energy, equal to the force of one Newton acting through one meter. 1 Watt is the power of a Joule of energy per second Power = Current x Voltage (P = I V) 1 Watt is the power from a current of 1 Ampere flowing through 1 Volt. 1 kilowatt is a thousand Watts. 1 kilowatt-hour is the energy of one kilowatt power flowing for one hour. (E = P t). 1 kilowatt-hour (kWh) = 3.6 x 106 J = 3.6 million Joules 1 calorie of heat is the amount needed to raise 1 gram of water 1 degree Centigrade. 1 calorie (cal) = 4.184 J (The Calories in food ratings are actually kilocalories.) A BTU (British Thermal Unit) is the amount of heat necessary to raise one pound of water by 1 degree Farenheit (F).

1 British Thermal Unit (BTU) = 1055 J (The Mechanical Equivalent of Heat Relation) 1 BTU = 252 cal = 1.055 kJ 1 Quad = 1015 BTU (World energy usage is about 300 Quads/year, US is about 100 Quads/year in 1996.) 1 therm = 100,000 BTU COMMON BIO FUELS AND THEIR ENERGY CONTENT- See chart… Energy Only 10% of energy in a light bulb is used to create light. Ninety percent of a light bulb’s energy creates heat. Compact fluorescent light bulbs (CFLs), on the other hand, use about 80% less electricity than conventional bulbs and last up to 12 times as long.g There are two basic groups of energy: renewable energy (biomass, geothermal, solar, water, and wind power) and nonrenewable (fossil fuels coal, oil, natural gas, nuclear). Three quarters of the world’s energy is generated by burning fossil fuels.h Lighting currently accounts for about 20% of U.S.

electricity consumption.h More than 1/5 of the world’s primary energy is used for transport, followed by industry, construction, and agricultures. Much is in the form of gasoline, of which nearly 792.5 million gallons is burned every day.e A “watt” is a unit of power that measures the rate of producing or using energy. The term was named after Scottish engineer James Watt (1736-1819), who developed an improved steam engine. Watt measured his engine’s performance in horsepower. One horsepower equaled 746 watts.e A hurricane releases 50 trillion to 200 trillion watts of heat energy.

This is as much energy as a 10-megaton nuclear bomb exploding every 20 minutes.b Countries with World’s Most Oil Reserves e Countries with World’s Most Natural Gas Reserves e Countries with World’s Most Coal Reserves e Countries with World’s Highest Oil Production d Countries with World’s Highest Oil & Total Fuel Consumption d Energy Use of Common Household Appliances g Energy Use of Common Household Appliances g Sources of Energy g Global Warming Without the atmosphere to create a greenhouse-type effect, the average temperature on Earth would be just 5° Fahrenheit (F).g Natural levels of CO2 in the atmosphere have varied throughout history between 180 and 300 parts per million (ppm). Today’s CO2 levels hover around 380 ppm, representing a 25% increase over the highest recorded natural levels.b Fossil fuel burning currently adds nearly six billion tons of CO2 to the atmosphere every year.

Only half of this CO2 is removed by forests and oceans.e Rampant deforestation currently causes 20% of the world’s global warming pollution by prohibiting the reabsorption of CO2.c The earth’s atmosphere now contains 40% more CO2 than before the Industrial Revolution.g The United States represents less than 5% of the world’s population, yet Americans account for 25% of the world’s commercial energy consumption and 22% of the world’s industrial emissions of CO2.e Nuclear Power Today, 104 nuclear plants supply about 20% of the United State’s electricity. The oldest plants have been operating since before 1979. There have been no new sites built since the Three Mile Island disaster (1979).a In the United States, radioactivity is often measured in rems. However, most countries currently use the sievert (Sv) to measure radioactivity. One sievert is equal to 100 rems. The nuclear waste from an entire reactor gives off about 10,000 rems per hour, even 10 years after it was first used in a nuclear plant.

A human who is exposed to 500 rems at one time will die.d Waste from the 1979 Three Mile Island accident is stored in Idaho, even though Idaho has never had a commercial reactor. Illinois has the most spent nuclear fuel of any other state in the U.S. at 9,301 tons. It is followed by Pennsylvania (6,446 tons), South Carolina (4,290), and New York and North Carolina (3,780 tons each).a The Sun produces an enormous amount of energy from its nuclear reactions that change hydrogen into helium. In the process, the Sun loses over 4 million tons of mass—every second.h Just removing a person’s outer clothing can remove 90% of the radioactive material after a disaster.f Before Fukushima Daiichi nuclear disaster in 2011, the International Energy Agency predicted that nuclear plants would add 360 gigawatts of generating capacity by 2035.

After Fukushima, the IEA halved those estimates.e Top Uranium Producers in the World (2006) h Number of Nuclear Warheads (2007) h Nuclear Timeline a Pollution Americans buy over 29 million bottles of water every year. Making all those bottles uses 17 million barrels of crude oil annually, which would be enough fuel to keep 1 million cars on the road for one year. Only 13% of those bottles are recycled. Plastic bottles take centuries to decompose—and if they are burned, they release toxic byproducts such as chlorine gas and ash containing heavy metals.g More oil is seeped into the ocean each year as a result of leaking cars and other non-point sources than was spilled by the Exxon Valdez.d Each person in the U.S. produces about 4 pounds (2 kg) of garbage a day.x A car from 1985 emits approximately 38 times more carbon monoxide than a 2001 model. BMWs were the most environmentally friendly, while Chrysler and Mitsubishi were the worst polluters.

Additionally, cars that get better gas mileage also pollute less.t For every 1 million tons of oil that is shipped, about 1 ton is spilled.d Los Angeles International Airport emits approximately 19,000 tons of carbon dioxide—a month. The roughly 33,000 planes that fly in and out of the airport each month release about 800,000 tons of carbon dioxide.p Recycling Burying coffins also means that 90,272 tons of steel, 2,700 tons of copper and bronze, and over 30 million feet of hard wood covered in toxic laminates are also buried per year. However, a British company called “Ecopod” offers coffins made from 100% recycled paper.b The United States makes up only 4% of the world’s population, yet it is the number one producer of garbage. In 2006, Americans generated more than 250 million tons of garbage.g Canada produces 31 million tons of garbage per year. The economic downturn in 2008 was devastating for the recycling industry.

Cardboard that sold for $135 a ton in September now sells for $35 a ton, and plastic bottles fell from 25 cents a pound to 2 cents a pound. What once was a multi-million dollar revenue is now turning into a liability for many cities.a Many industries and manufacturers’ demand for scrap, paper and other recyclables, dropped as consumer demand for new cars, houses, and appliances also dropped. Each year, Americans throw out enough soda pop cans bottles to reach to the moon and back—twenty times.h Cigarette butts and filters take 12 years to biodegrade. An aluminum can takes between 200 to 500 years to biodegrade. Plastic diapers and sanitary pads take between 500-800 years. Styrofoam takes more than 5,000 years. And it would take a glass bottle 1 million years to biodegrade.h A single 20-watt compact fluorescent bulb, compared to a 75-watt incandescent light bulb, saves about 550kWh of electricity over its lifetime.

If the electricity is produced from a coal-fired power plant, that savings represents about 500 pounds of coal. If every household in Wisconsin replaced one 75-watt incandescent light bulb with a 20-watt compact fluorescent bulb, enough electricity would be saved that a 500-megawatt coal-fired plant could be retired. To find out, visit: Home Energy Saver™ (HES) . Btu Content of Common Energy Units 1 barrel (42 gallons) of crude oil = 5,800,000 Btu 1 gallon of gasoline = 124,238 Btu (based on U.S. consumption, 2008) 1 gallon of diesel fuel = 138,690 Btu 1 gallon of heating oil = 138,690 Btu 1 barrel of residual fuel oil = 6,287,000 Btu 1 cubic foot of natural gas = 1,027 Btu (based on U.S.

consumption, 2008) 1 gallon of propane = 91,033 Btu 1 short ton of coal = 19,977,000 Btu (based on U.S. consumption, 2008) 1 kilowatthour of electricity = 3,412 Btu . Examples of Converting Different Energy Sources to Btu Answer: When you convert the fuels into the same units, you see that residual fuel oil now costs more than natural gas. You decide to switch to natural gas to save money.

SI Units SI Units Navigation/Menü: Links auf weitere Seiten dieser Website und Banner length metre (meter): m (the correct English spelling of the unit is "metre", but the variant "meter" is frequently used in the United States) SI Prefixes exponent (base 10) of decimal numbers: E n = 10n Factor Prefix Symbol 1024 E 24 yotta Y 1021 E 21 zetta Z 1018 E 18 exa E 1015 E 15 peta P 1012 E 12 tera T 109 E 9 giga G 106 E 6 mega M 103 E 3 kilo k 102 E 2 hecto h 101 E 1 deca da 10-1 E -1 deci d 10-2 E -2 centi c 10-3 E -3 milli m 10-6 E -6 micro µ 10-9 E -9 nano n 10-12 E-12 pico p 10-15 E

-15 femto f 10-18 E-18 atto a 10-21 E-21 zepto z 10-24 E-24 yocto y (Please note: all units to the right of the slash are actually in the denominator!) Frequency pascal: Pa = N/m2 = kg/m s2 Energy, work, quantity of heat joule: J = N m = m2 kg/s2 watt: W = J/s = m2 kg/s3 Quantity of electricity, electric charge coulomb: C = s A volt: V = W/A = m2 kg/s3 A farad: F = C/V = s4 A2/m2 kg ohm: Omega = V/A = m2 kg/s3 A2 siemens: S = A/V = s3 A2/m2 kg weber: Wb = V s = m2 kg/s2 A Magnetic flux density, magnetic induction tesla: T = Wb/m2 = kg/s2 A henry: H = Wb/A = m2 kg/s2 A2 lux: lx = lm/m2 = cd sr/m2 pascal second: Pa s = kg/m s metre

 newton: N m = m2 kg/s2 newton per metre: N/m = kg/s2 watt per square metre: W/m2 = kg/s3 joule per kelvin: J/K = m2 kg/s2 K Specific heat capacity, specific entropy joule per kilogram kelvin: J/kg K = m2/s2 K joule per kilogram: J/kg = m2/s2 watt per metre kelvin: W/m K = m kg/s3 K joule per cubic metre: J/m3 = kg/m s2 volt per metre: V/m = m kg/s3 A coulomb per cubic metre: C/m3 = s A/m3 Electric displacement, electric flux density coulomb per square metre: C/m2 = s A/m2 farad per metre: F/m = s4 A2/m3 kg henry per metre: H/m = m kg/s2 A2 joule per mole: J/mol = m2 kg/s2 mol Molar entropy, molar heat capacity joule per mole kelvin: J/mol K = m2 kg/s2 K mol coulomb per kilogram: C/kg = s A/kg gray per second: Gy/s = m2/s3

Question: What is the SI unit of energy?
Answer: Joule